1. Field of the Invention
The present invention relates to an ophthalmologic image pickup apparatus used in an ophthalmologic doctor's office and the like.
2. Related Background Art
Up to now, according to an eye fundus camera, the illumination and the image pickup of an eye fundus are conducted using a common objective lens. Among illumination light, reflected light from the surface of the objective lens, a smudge or a scratch on its surface, a bubble in the lens, etc, is directly incident into an image pickup optical system as ghost light and overlapped with an eye fundus image. Therefore, the reflected light becomes a cause in which a ghost image is generated. In order to suppress the generation of the ghost light, a strict standard is applied to an appearance concerning, for example, a bubble in the lens and a scratch on its surface; an antireflective film to which a strict specification is applied is used; and a black spot is provided in an illumination optical system.
Also, with respect to ghost light resulting from parts except the object lens, in order to suppress the generation of such light, the selection and special processing of parts, the limitation on design, postprocessing to the optical systems, and the like are conducted.
However, in the above-mentioned conventional example, even if a black spot is provided on an optical path, there is no effect using the black spot with respect to light diffused in an optical member between the black spot and the objective lens. Accordingly, there is a problem that it is difficult to completely eliminate the ghost light. Therefore, a standard required to the objective lens and the like becomes stricter, so that a part cost becomes higher or it takes much time for adjustment and assembly operations. Thus, there is a problem that a remarkable increase in assembly cost is caused.